Bilingual Alzheimer's Disease

 描述（由申请人提供）：该项目调查双语和阿尔茨海默病（AD）对语言和认知处理的联合后果，目标是塑造双语的心理语言模型（目标1），测试AD中认知下降的模型（目标2），并表征双语AD典型的认知障碍的概况（目标3）。最初5年的资助数据揭示了AD中双语下降的意外模式，并表明双语者在通常用于诊断AD的神经心理测试中表现不同于单语者。这些结果挑战模型的双语和认知能力下降的AD，目前不占双语AD的认知变化模式，他们强调需要进一步研究的因素，是已知的影响双语语言处理的影响，在双语AD的介绍。我们认为双语语言处理的三个主要帐户，以获得有关AD的双语下降的预测，同时也旨在确定哪种语言，哪些任务，以及哪些测试条件下产生的西班牙语-英语双语AD和匹配的认知健康对照之间的最大差异。作为这一奋进的一部分，我们建议扩大我们的调查双语广告的语言缺陷，从单个单词的生产，也检查生产的连接语音和口头清单记忆。拟议的研究提供了一个独特的测试模型的认知能力下降的AD，其中，当考虑在演唱会与不同的双语处理模型，导致不同的预测双语AD的双语变化。通过测试这些模型，我们的目标是确定哪种认知机制是双语AD语言衰退的原因（语义处理，检索困难或执行控制），以阐明执行控制在双语语言处理中的作用，并可能确定双语对认知衰退的保护作用，以及独特的认知机制。 双语者的AD标志物。使用双语语言能力的客观措施，每项研究将探讨双语如何影响整个连续体从低到高水平的熟练程度的表现。拟议的研究将继续进行系统的研究计划，旨在描述双语AD中认知缺陷的典型表现，同时带来独特的证据来证明AD中双语语言处理和认知下降的模型。拟议的研究将提供一个理论框架，从中制定更好的双语评估措施，他们将有进一步的实际影响，通过确定条件，最大限度地减少语言之间的干扰，并允许双语AD流利地说，因为他们可以。

 DESCRIPTION (provided by applicant): This project investigates the joint consequences of bilingualism and Alzheimer's disease (AD) for linguistic and cognitive processing, with the goals of shaping psycholinguistic models of bilingualism (Aim 1), testing models of cognitive decline in AD (Aim 2), and characterizing the profile of cognitive impairments typical of bilingual AD (Aim 3). Data from an initial 5 years of funding revealed unexpected patterns of dual-language decline in AD, and suggested that bilinguals perform differently from monolinguals on neuropsychological tests often used to diagnose AD. These results challenge models of bilingualism and cognitive decline in AD, which currently do not account for patterns of cognitive change in bilingual AD, and they underscore the need to further investigate how factors that are known to affect bilingual language processing influence the presentation of AD in bilinguals. We consider three major accounts of bilingual language processing to derive predictions about dual-language decline in AD, while also aiming to identify which language, which tasks, and which testing conditions produce the greatest differences between Spanish-English bilinguals with AD and matched cognitively healthy controls. As a part of this endeavor, we propose to extend our investigation of language deficits in bilingual AD from single word production to also examine production of connected speech and verbal list memory. The proposed studies provide a unique test of models of cognitive decline in AD, which, when considered in concert with different bilingual processing models, lead to different predictions about dual-language change in bilingual AD. By testing these models, we aim to identify which cognitive mechanism is responsible for linguistic decline in bilingual AD (semantic processing, retrieval difficulty, or executive control), to shed light on the role of executive control in bilingual language processing and, possibly, to identify protective effects of bilingualism against cognitive decline, and unique markers of AD in bilinguals. Using objective measures of bilingual language proficiency, each study will examine how bilingualism affects performance across the full continuum from low to high levels of proficiency. The proposed studies will continue a systematic program of research that aims to characterize the typical presentation of cognitive deficits in bilingual AD, while bringing unique evidence to bear on models of bilingual language processing and cognitive decline in AD. The proposed studies will provide a theoretical framework from which to develop better assessment measures for bilinguals, and they will have further practical implications by identifying conditions that minimize interference between languages and allow bilinguals with AD to speak as fluently as they can.